1. Field of the Invention
The subject invention relates to a verification device for use in gaming chips typically used in casinos, for ID or credit cards and for security paper such as banknotes, for anticounterfeit security protection.
2. Description of the Prior Art
While the invention can be employed to facilitate the identification of any article not incorporating the waveguide device, the best use is the rapid identification of plastic gaming chips or casino chips that have molded into them the optical variable waveguide.
Casinos converts legal tender into gaming chips of various denominations. These chips typically contain identifying techniques such as base color, color coded edge spots, colored embossing and printed graphics in the center of the chip. Counterfeiting these chips is a problem because the chip can be painted different colors to match higher denominations and the graphics reproduced by color copy machines or personal computers and laminated to the chip.
Graves in U.S. Pat. No. 3,953,932 attempts to deter the unauthorized duplication of gaming chips by molding a transparent layer over the more opaque color insert, whereas Howard in U.S. Pat. No. 4,026,309 provides fluorescent strips along the periphery of the gaming chip to allow machine scanning of the chips denomination. Modlar in U.S. Pat. No. 5,361,885 provides an anticounterfeiting feature using a sandwiched light-conducting or translucent layer terminating around the peripheral edge of chip.
It is known in the art of banknote and currency papers to incorporate a security thread embedded within the paper making it difficult to illicitly reproduce. The present waveguide either in a round or planar strip configuration can be used as an embedded security thread in paper. Plastic security strip or thread is shown by Harbaugh in U.S. Pat. No. 5,419,424 for use in security or currency paper. Such threads contain reflective or transmitted micro-printing, electrically conductivity, and/or fluorescence. A diffraction grating authenticating device that operates as a diffractive subtractive color filter responsive to the angle of incidence of the polychromatic illuminating light is shown by Sandercock in U.S. Pat. No. 4,526,466 and by Knop et al. in U.S. Pat. No. 4,484,797. Other state-of-the-art authentication devices for currency paper is that developed by Berning et al. in U.S. Pat. No. 4,930,866 involves a thin film color shifter that are applied as a stamp or printed as an ink.
It is typical for credit, identification and data cards to contain optical anticounterfeit features such as holograms, colored micro-graphics, thin film color shifters and pictures to permit their authentication. A security means such as in Margolin in U.S. Pat. No. 4,682,794 comprising a plurality of optical fibers embedding into a credit card to form an unique code pattern. An security document comprising at least one embedded fiber optic using a core doped fluorescent fiber optic is disclosed by Camus in U.S. Pat. No. 4,710,614.